Mosaic virus can be kept under control through the use of milk sprays (Conacher, 1991). Conacher recommends 1 part of milk and 9 parts of water, in repeated applications, ten days apart. To control mildew, 1 part of milk and 2 parts of water are used. To cover 20m2 it is advised to use 0.5L of milk in 1L of water. Therefore a hectare (10 000m2) requires 250L of milk, which would be cost prohibitive. Potencies of Lac. ac. will act equally well at a fraction of the cost. (3)